This invention relates to a disk cartridge for containing, as an information recording medium, a disk such as an optical disk, photomagnetic disk, and magnetic disk, particularly to the improvement of a disk cartridge in which information can be recorded/reproduced on/from the disk contained in the cartridge.
As is well known, a disk cartridge contains a disk in a flat rectangular body such that the disk can be rotated freely. In the cartridge body, a discrimination hole which is unoccupied/occupied by a closing member is formed at a predetermined position.
The information is recorded/reproduced on/from a disk by a disk drive. The disk drive is provided with detecting means for detecting, in the state where the cartridge body is attached to the disk, whether the discrimination hole is occupied or unoccupied. The disk driving mode of the disk drive is set in accordance with the detection result.
Recently, a cartridge body having a disk insertion portion provided with a lid capable of opening/closing the cartridge body is formed at a distal end portion has been put into the market. Such a cartridge body has been developed to enhance the free degree in use of the disk such that the disk can be taken out of the cartridge to be independently used.
The lid of the cartridge body has a hole therein. The hole communicates with the discrimination hole when the lid is locked. In the cartridge body, a pin member as a closing member is inserted into the discrimination hole and the hole on the lid to occupy the holes such that the lid is not released.
The lid of the cartridge body can be released by removing the pin member from the holes. The pin member is formed integrally with supporting pieces at the inner periphery of the discrimination hole of the cartridge body so as to be supported thereby. This pin member can be removed from the cartridge body when the supporting pieces are cut by bending or breaking.
With this structure, when the discrimination hole and the hole in the lid are detected to be occupied by the pin member, the disk drive determines that the lid has been never released, that is, the disk contained in the cartridge body has been never taken out.
If the discrimination hole and the hole in the lid are detected not to be occupied by the pin member, the disk drive determines that the lid has been released, that is, the disk contained in the cartridge body has been taken out.
The disk driving mode of the disk drive is set in accordance with the determination. If the disk has been taken out from the cartridge body, there is more possibility that dust may be attached to the disk or the disk may be damaged in comparing with the case where the disk has not been taken out from the cartridge body.
The conventional disk drive is therefore designed to change the performance or function of each circuit block for recording/reproducing information, i.e., to change the disk driving mode, in accordance with whether or not the disk has been taken out, such that the information can be recorded/reproduced under the optimum condition most suitable for the disk on/from which the information is recorded/reproduced.
The supporting pieces for supporting the pin member in the conventional disk cartridge are, however, not suitable for normal use if easily broken due to the external force applied to the supporting pieces during the normal operation. On the other hand, if the supporting pieces cannot be easily cut when the pin member is desired to be manually removed from the apparatus, the supporting pieces cannot be said to be practical.
Accordingly, the structure or size of the supporting piece for supporting the pin member has been eagerly desired to be improved so as not to be easily broken by an external force applied to the disk drive during normal operation and so as to be easily cut when the pin member is intended to be manually removed from the apparatus.